package com.lhd.action.observer;

import java.util.ArrayList;
import java.util.List;

/**
 * @Author: liuhd
 * @Date: 2024/12/18 20:23
 * @Description: 抽象主题类
 */
public abstract class Up {
    protected List<Fan> fans = new ArrayList<>();
    public abstract void addFan(Fan fan);
    public abstract void delFan(Fan fan);
    public abstract void notifyFans(String msg);
}
